Improvement in geographical maps



UNITED STATES PATENT E. A. APGAR AND A. C. 'APGAIL OF PHlLADELPHlA,PENNSYLVANIA.

IMPROVEMENT IN GEOGRAPHICAL MAPS.

Specification formingpart of Letters Patent No. fd, dated October 16,1866.

To all 'whom it may concern:

Be it known that we, E. A. APGAR and A. C. APGAR, ot' Philadelphia,county of Philadelphia, and State of Pennsylvania, have invented a newand useful symbolic language for expressing the size of cities and theheights of hills, mountains, and plateaus,.and also an inproved Methodof Constructing Geographical and other Maps 5 and we do hereby declarethe same is fully described and represented in the followingspecilications and the accompanying drawings.

The nature of our invention consists in the use of such triangulationsand other geometrical figures t'or helps in inap-drawing', in which someone line in each case is selected and used for determining the lengthsof other lines about the tigure.

rlhe importance of our discovery and invention consists in determiningwhat line about the tig-ure to be constructed will best serve thepurpose ot' a measuring-unit. In order to serve such a purpose, it mustbe a convenient measure or multiple oi' other lines whose lengths are tobe determined by it. Ve claim vto have discovered for each ot' ourgeometrical iigures such a convenient measuring-unit, and to have madeuse of a new and highlyimportant method ot using this measuringunit forcompleting the figure.

The nature of our invention consists in a simple, comprehensive, andeasily retained symbolic language and mode of constructing maps for theuse of schools, whereby the pupil will be enabled, by a little practice,to draw and construct maps ot' States, continents, Ste., without the aidot' a copy, and to remember the population of. cities, the height ot'hills, mountain-peaks, and plateaus. Nor will the pupil require theknowledge necessary for the ordinar r system ot construction. Our methodis especially suited to the youthful capacity, but can be used withprotit by the older and more advanced pupils.

In the accompanying drawings, which form part of this specification,Figure l represents the triangulation of the continent in accordancewith our invention. Fig. 5, a table representing' the symboliccharacters used.

rlhe following is a further explanation ot" our invention. Inconstructingthe triangulation of North America, the line A B is taken asthe base ormeasuring-unit by which the lengths ot'other lines aredetermined. This rst or base line is biseeted at O, and the line C D isdrawn at right angles to and one-haltl as long as A B. The points A andD, and D and B are next connected, and then the line (j D is extended tothe left, making the whole line D E equal in length to A D or D B. Thepoints A and E and E and B are connected with straight lines, and theare E B, drawn with D as center. A E is bisected at F, and upon A F isconstructed the equilateral triangle A FG.

A skeleton map is thus produced which determines the position of themost important points upon the coastline, and also the general contourofthe continent. The lines composing this geometrical expression of thecontinent are next bisected, trisected, or quadrisected, as the easedemands, for the purpose of determining the position of other importantpoints about or within the continent. This geometrical expression of thecontinent is easily constructed, the relation between it and thecontinent readily remembered, and upon it the map may accurately bedrawn. rlhere is no use made of mathematical instruments and noreference to degrees or angles other than right angles. Its use enablesthe pupil to draw from memory.

Triangulations similarly constructed are prepared for aids in drawingother continents, sections ot' continents, islands, die.

From the above it will be seen that we have invented a system ot'oft-hand map-drawing, (the necessity of which professional experiencehas taught us, in preference to the abstruse and complicated methods inpresent use,) whereby a knowledge ot' geography, through a plain andeasy system ot' language and construction, may be acquired by theyounger pupils without waiting for acquaintance with the higher branchesor use ot' mathematical instruments; and thus it places geography sideby side with the reading lessons, tor which object our invention, wetrust, has reached the desideratum.

XVe therefore distinctly claim as original with us and desire to secureby Letters Patentl. The use for inap-drawing of such geometrieal figuresas are constructed by taking in each case some one line as a measuringunit, by means of which the lengths of other lines about the ligure aredetermined. We do not claim the use of those figures which areconstructed by the measurement of angles.

2. The trisecting and bisecting of certain lines about our geometricalfigures for the purpose of determining the positions of certainprominent points along the coast lines ot the continents.

3. That symbolic language for maps in which dots and lines, arrangedsubstantially as described, are used to represent certain .numbers,Whether of population of cities or the height of isolated hills,mountain-peaks, or plateaus in feet or miles or other units ,ofmeasurement.l

E. A. APGAR. A. C. APGAR.

Witnesses J. B. GOWPERTHWMT, Guns. Davis.

